Read 220V with 8-Channel I2C MCP23008 Optically Isolated Digital Input with I2C Interface

Hello there. I need to read 220V signal with PR33-19 how can I do this?

Thanks in advance.

This controller accepts a input voltage range of 3V to 24V AC or DC. I would suggest using a simple wall transformer that converts 220V to 12V. Hope this helps. Please let us know if you have more questions.

I was think about that but because i read this on the product information I like to know more.

It is possible to increase the input voltage by simply adding more resistance in series with the input signal.

While this is possible, it is not advised. You run the risk of damaging the opto if your math calculations are off by even a little bit. There will also be some heat issues that you will need to handle. Galvanic currents leaching across the board may also interfere with logic, which may cause undesired results or damage. The best solution is to use a proper transformer.

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Very good explanation.

Best regards.